1. Field of the Invention
This invention relates generally to a battery exchange system, and more specifically, to a battery exchange system for replacing a depleted battery pack in a battery powered vehicle with a fresh battery pack and method therefor.
2. Description of the Prior Art
Currently there are numerous devices and methods for removing a depleted battery pack from a battery powered vehicle and replacing the battery pack with a fresh battery pack. U.S. Pat. No. 5,187,423 discloses an apparatus, for replacing a discharged battery pack from a battery powered vehicle, which uses a forklift type device for lifting and moving the discharged battery pack. The problem with this apparatus, and other battery replacement systems which use a forklift type device for lifting and moving the battery pack, is that the use of a forklift type device raises the possibility of damage to the battery pack as well as damage to the battery powered vehicle. Inexperience or inattentive forklift operators have a tendency to misalign the lifting plates of the forklift thereby stabbing the battery pack or the battery powered vehicle with the lifting plates.
Other types of battery exchange systems use a chainfall or block and tackle hoist arrangement to move the battery pack. These types of systems require an operator to connect the hoist to the discharged battery pack in the battery powered vehicle, lift the battery pack out of the battery powered vehicle, and move the hoist to a position to off load the spent battery. The hoist is then moved to a position where a fully charged battery pack is located. The hoist is connected to the fully charged battery pack, moved to a position next to the battery powered vehicle, and the fully charged battery pack is lowered into the battery powered vehicle. While these types of systems do work, they require a tremendous amount of time and effort on the part of the operator in order to exchange the battery pack.
Another type of battery exchange system uses a hoist in conjunction with a roll off dolly. U.S. Pat. No. 4,450,400 discloses a battery exchange system which uses a hoist like structure in combination with a support mechanism having a plurality of rollers to replace a discharged battery pack in a battery powered vehicle. In this system, a discharged battery pack in a battery powered vehicle is rolled off a support mechanism having a plurality of rollers onto a hoist like structure also having a support mechanism having a plurality of rollers. The hoist is then moved to a location where the discharged battery pack is rolled off of the support mechanism and placed in a location for recharging the depleted battery pack. The hoist is then moved to a new location where a charged battery pack is rolled onto the support mechanism of the hoist. The hoist is then moved to a position next to the battery powered vehicle where the charged battery pack is rolled off of the support mechanism of the hoist and onto a support mechanism of the battery powered vehicle. While the plurality of rollers on the support mechanism may aid in the replacement of the battery pack, this type of system still requires a great deal of effort on the part of an individual who is attempting to replace the depleted battery pack. A typical battery pack used on a battery powered vehicle may weigh anywhere from 1,500 lbs to over 2,000 lbs. Thus, even if the battery pack is on a plurality of rollers, the battery pack would still be very difficult to move.
Therefore, a need existed to provide an apparatus and method for replacing a depleted battery pack in a battery powered vehicle and replacing it with a fresh battery pack having stored energy. The apparatus and method must be capable of replacing the battery pack in a short amount of time and with minimal effort on the part of an individual who is operating the battery exchange apparatus.